# Time Series Anomaly Detector Upload CSV or JSON time series data, detect anomalies with Z-Score and IQR methods, and return a chart-backed report > Canonical page: https://elysiatools.com/en/tools/time-series-anomaly-detector - **Category:** Data Analysis - **Keywords:** time series, anomaly, z-score, iqr, csv, trend ## Overview The Time Series Anomaly Detector is a powerful utility that analyzes CSV or JSON data to identify unusual spikes, drops, or outliers. By applying statistical methods like Z-Score and Interquartile Range (IQR), it automatically flags anomalies and generates a visual HTML report with a rendered chart, making it easy to spot irregular trends in your data. ## Inputs - **CSV or JSON Input** (textarea): timestamp,value 2026-03-01T00:00:00Z,10 2026-03-02T00:00:00Z,12 - **Data File** (file) - **Timestamp Column** (text) - **Value Column** (text) - **Detection Method** (select) - **Z-Score Threshold** (number) - **Seasonality Window** (number) ## When to use - When you need to quickly identify abnormal spikes or drops in daily metrics like revenue, traffic, or active users. - When analyzing server logs or monitoring data to pinpoint latency issues or downtime events. - When cleaning historical datasets to remove or investigate statistical outliers before training machine learning models. ## How it works - Upload your time series data as a CSV, JSON, or Excel file, or paste it directly into the text area. - Specify the column names for your timestamps and values, then select your preferred detection method (Z-Score, IQR, or both). - Adjust the Z-Score threshold and seasonality window to fine-tune the sensitivity of the anomaly detection. - Generate a comprehensive HTML report featuring an interactive chart and a summary of all flagged anomaly segments. ## Use cases - E-commerce managers tracking daily sales to detect unexpected revenue drops or viral product spikes. - DevOps engineers monitoring server CPU usage and latency to identify infrastructure bottlenecks. - Financial analysts reviewing daily stock prices or transaction volumes to spot irregular trading activities. ## Frequently asked questions ### What data formats are supported? You can upload CSV, JSON, or Excel files, or paste raw CSV/JSON text directly into the input field. ### What is the difference between Z-Score and IQR? Z-Score measures how many standard deviations a data point is from the mean, which is great for normally distributed data. IQR uses quartiles to find outliers and is more robust against extreme values. ### How does the seasonality window work? The seasonality window allows the tool to account for recurring patterns over a specified number of periods, helping to separate normal seasonal fluctuations from true anomalies. ### Can I customize the sensitivity of the detection? Yes, you can adjust the Z-Score threshold between 1 and 6. A lower threshold flags more points as anomalies, while a higher threshold only flags extreme outliers. ### What does the output report include? The tool generates an HTML report containing a visual chart of your time series, highlighted anomaly markers, trend slopes, and a summary of contiguous anomaly segments. ## Related tools - [Time Series Forecast & Seasonality Analyzer](https://elysiatools.com/en/tools/time-series-forecast-seasonality-analyzer): Forecast future periods from CSV or JSON time-series data and inspect trend, seasonal, and residual decomposition in one report - [JSON-LD Generator from CSV](https://elysiatools.com/en/tools/json-ld-generator-from-csv): Turn CSV or Excel rows into Schema.org JSON-LD for articles, products, or events, with validation-ready output for SEO workflows - [XLSX Multi Sheet Splitter](https://elysiatools.com/en/tools/xlsx-multi-sheet-splitter): Split a multi-sheet workbook into independent files by sheet name, with ZIP output - [Barcode Batch Generator](https://elysiatools.com/en/tools/barcode-batch-generator): Batch generate Code 128, EAN-13, UPC-A, ITF-14, QR Code, and Data Matrix outputs from CSV or multiline text - [CSV / Excel Diff Tool](https://elysiatools.com/en/tools/csv-excel-diff-tool): Compare two CSV or XLSX datasets and export a PDF report with row, column, and cell-level differences - [XLSX CSV Batch Converter](https://elysiatools.com/en/tools/xlsx-csv-batch-converter): Batch convert CSV/TSV to XLSX or convert XLSX back to CSV/TSV with delimiter and encoding handling - [XLSX Formula Injector](https://elysiatools.com/en/tools/xlsx-formula-injector): Fill formulas down worksheet columns and optionally lock formula cells for protected, template-friendly Excel workbooks - [Text to Excel Converter](https://elysiatools.com/en/tools/text-to-excel): Convert various text formats to Excel with customizable parsing and formatting options ## Samples - [XLS Samples](https://elysiatools.com/en/samples/xls-samples): Sample legacy Excel (XLS) files for binary spreadsheet parsing and import tests - [XLSX Samples](https://elysiatools.com/en/samples/xlsx-samples): Sample XLSX spreadsheets for worksheet parsing and data extraction testing - [CSV Samples](https://elysiatools.com/en/samples/csv-samples): Sample CSV files with various data types, sizes, and complexity levels - [Python Samples](https://elysiatools.com/en/samples/python): Essential Python code examples and Hello World demonstrations ## Related content - [Data Quality, Dedupe, and Anomaly Detection Tools](https://elysiatools.com/en/hubs/data-quality-anomaly-workflows): Profile CSV/JSON datasets, compare spreadsheet versions, find duplicates, outliers, missing-value issues, referential breaks, and time-series anomalies in one data-quality workflow hub. - [JSON Interchange and Format Translation Tools](https://elysiatools.com/en/hubs/json-convert): Compare JSON conversion tools for CSV, YAML, TOML, GraphQL, XML, Markdown, Excel, BSON, EDN, and related structured formats in one hub. - [Text Case, Encoding, and Normalization Conversion Tools](https://elysiatools.com/en/hubs/text-convert): Compare text case conversion, character-width conversion, encoding conversion, quoted-printable handling, and inline text normalization tools in one hub. - [JSON Inspection, Diff, and Transformation Tools](https://elysiatools.com/en/hubs/json-utility): Compare JSON formatting, diffing, path inspection, schema validation, merging, transformation, and export tools in one hub for API and data workflows.